With the increase in mining depth and intensity, the threat of rockburst caused by high stress in stope to coal mining (CM) safety production is becoming ever more serious. However, it is more ...difficult to predict and prevent rockburst in deep mining coal seams under complex environments. Firstly, this paper analyzes the detection requirements in the tested environment and designs a new multi-parameter monitoring platform for CM-induced rockburst through wireless sensor network, communication protocol and Internet of things (IoT) technology. Then, two improvements are made to the original faster region-convolutional neural network (Faster R-CNN). The first point is to replace Faster R-CNN’s common feature extraction network. The second point is to fuse the region proposal network structure of Faster R-CNN with feature pyramid network and combine Faster R-CNN with probabilistic neural network (PNN). Finally, the proposed system is tested. The outcomes corroborate that under the complex external geographical environment, the communication distance of the proposed CM-induced rockburst-oriented multi-parameter monitoring platform is far, and the proposed system meets the actual needs. The prediction results of the original PNN show that the prediction error rate of the training is 0.999%, and the prediction error rate of the test set is 0.995%. The prediction results based on PNN + optimized Faster R-CNN show that the prediction error rate of training is 0.623%, and the prediction error rate of the test set is 0.409%. Therefore, the prediction effect of PNN + optimized Faster R-CNN is better than PNN. The proposed CM-induced rockburst-oriented dynamic pressure prediction system provides some ideas for applying IoT and deep neural network technology in the CM industry.
Abstract
The development of biomedical glues is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, i.e. strong adhesion and adaption to ...remodeling processes in healing tissue. Here, we report a biocompatible and biodegradable protein-based adhesive with high adhesion strengths. The maximum strength reaches 16.5 ± 2.2 MPa on hard substrates, which is comparable to that of commercial cyanoacrylate superglue and higher than other protein-based adhesives by at least one order of magnitude. Moreover, the strong adhesion on soft tissues qualifies the adhesive as biomedical glue outperforming some commercial products. Robust mechanical properties are realized without covalent bond formation during the adhesion process. A complex consisting of cationic supercharged polypeptides and anionic aromatic surfactants with lysine to surfactant molar ratio of 1:0.9 is driven by multiple supramolecular interactions enabling such strong adhesion. We demonstrate the glue’s robust performance in vitro and in vivo for cosmetic and hemostasis applications and accelerated wound healing by comparison to surgical wound closures.
•The Industry-university-research Collaborative Innovation Efficiency is studied.•The Malmquist index was used to decompose the ICIE.•Regional differences in efficiency collaborative innovation are ...revealed.•The impact of ICIE on carbon emissions was studied.•ICIE influences carbon emissions by the mediation of green innovation capabilities.
Industry-university-research cooperation is an important component of the national innovation system. It is of great significance to promote scientific and technological achievements, promote industrial transformation and upgrading, and build a country that is powerful in science and technology. As an organizational form of technological progress, the efficiency of industry-university-research (IUR) cooperation can also affect carbon emissions. Based on panel data of 30 provinces in China from 2009 to 2017, this paper uses data envelopment analysis (DEA) to study regional differences in industry-university-research collaborative innovation efficiency (ICIE) and the impact of carbon emissions. The results show that (1) the average efficiency of China's industry-university-research collaboration innovation is 0.65, and many provinces have not reached the effective frontier. Compared with the efficiency of South China at the regional level, ICIE in North China, Northeast China, Northwest China, and Southwest China is low, and the efficiency of ICIE needs to be further improved. (2) Based on the Malmquist index (MI) decomposition of ICIE, the overall ICIE in China is increasing, of which technological progress (TECH) is the main driving factor. (3) According to the results of the regression model, China's carbon emissions exhibit a path dependence, and improving ICIE can reduce carbon emissions. (4) Green innovation plays an intermediary role. The improvement of ICIE promotes the improvement of green innovation capabilities, and the improvement of green innovation capabilities can effectively suppress carbon emissions.
Liquid-liquid phase separation is considered a generic approach to organize membrane-less compartments, enabling the dynamic regulation of phase-separated assemblies to be investigated and pivotal ...roles of protein posttranslational modifications to be demonstrated. By surveying the subcellular localizations of human deubiquitylases, USP42 was identified to form nuclear punctate structures that are associated with phase separation properties. Bioinformatic analysis demonstrated that the USP42 C-terminal sequence was intrinsically disordered, which was further experimentally confirmed to confer phase separation features. USP42 is distributed to SC35-positive nuclear speckles in a positively charged C-terminal residue- and enzymatic activity-dependent manner. Notably, USP42 directs the integration of the spliceosome component PLRG1 into nuclear speckles, and its depletion interferes with the conformation of SC35 foci. Functionally, USP42 downregulation deregulates multiple mRNA splicing events and leads to deterred cancer cell growth, which is consistent with the impact of PLRG1 repression. Finally, USP42 expression is strongly correlated with that of PLRG1 in non-small-cell lung cancer samples and predicts adverse prognosis in overall survival. As a deubiquitylase capable of dynamically guiding nuclear speckle phase separation and mRNA splicing, USP42 inhibition presents a novel anticancer strategy by targeting phase separation.
This work investigates the interfacial bonding properties between calcium silicate hydrate and fibers at the micro-level.
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•The interfacial shear strength between C-S-H and polymer ...fibers is closely related to the fiber types.•Ca atoms in the interface play an important role in the interfacial bonding interactions.•H bonds provide contribution for enhancing the interfacial bonding strength.
The macroscopic mechanical performance of fiber reinforced concrete (FRC) is determined by the interfacial microstructure and the interfacial bonding properties between hydration products and fibers. This research is dedicated to study the interfacial shear strength, structure and dynamics between calcium-silicate-hydrate (C-S-H) and polymer fibers. To better understand the effects of fiber types on the interfacial shear strength, three kinds of fibers were investigated, including polypropylene (PP), polyvinyl alcohol (PVA) and polyacrylic acid (PAA). The calculation results indicate that the interfacial shear strength is closely related to the fiber types. The interfacial shear strength of fibers restricted in the C-S-H substrate was arranged in the following order PAA fiber > PVA fiber > PP fiber. After measuring the interfacial shear strength, the static molecular structure and dynamics properties, especially at the interface between the fiber and the C-S-H matrix, the cause for the interfacial shear strength discrepancy between different fibers was uncovered. It shown that the Ca atoms in the interface play an important role in the interfacial bonding interactions by the formation of OCSH-Ca-Opolymer connection. The H bonds can be formed between PAA/PVA fibers and C-S-H substrate, also provide some contribution for enhancing the interfacial bonding strength. The chemical bond stability revealed that the interfacial bonding strength of three fibers follows the order of PAA fiber > PVA fiber > PP fiber, which is consistent with the order of interfacial shear strength.
Replacing cement with large amounts of fly ash in engineered cementitious composites (ECC) is one of the win-win measures to enhance matrix ductility and effectively reduce carbon emissions. However, ...the high content of fly ash undoubtedly makes the mechanical properties of ECC lower, resulting in its performance at high temperature to be questioned. To solve this problem, this paper combines experiments and molecular dynamics study to fully explore and innovatively explain the performance of ECC exposed to different temperatures (20 °C, 200 °C, 400 °C, 600 °C and 800 °C) from the aspects of macroscopic mechanical properties, microstructural characteristics and molecular-scale interfaces. From 20 °C to 800 °C, the mechanical properties first increase and then decrease significantly. SEM shows the changes in the microscopic morphology at elevated temperatures, such as the increase of cracks and pores in the matrix, and the melting of the PVA fibers. TG/DSC and XRD illustrate the phase transformation at different temperatures. 29Si NMR demonstrates the decomposition of hydration products and the depolymerization of silicate chains at higher temperatures. Additionally, molecular dynamics study is carried out to characterize the interaction between PVA fibers and C–S–H gel at a molecular scale as a function of temperature. With the increase of temperature, the morphology of C–S–H gradually changes from layered structure to spherical structure, the water molecules between the C–S–H layers gradually diffuse to the C–S–H channel, and PVA chains are present by disordered distribution. The simulated results have a good agreement with experimental results and further explain the damage mechanism of ECC at elevated temperatures on the nano-scale level.
•AlM2 barometer in Na-amphibole can only be used in act- & ab-bearing assemblage.•The P–T estimates for the blueschists yield intermediate P/T facies series.•Protoliths of the blueschists are formed ...later than Late Paleozoic–Early Mesozoic.•The blueschists may be new type attributed to closure of limited ocean basins.
Blueschists in central Inner Mongolia are distributed as layers and blocks in mélanges including the southern zone in Ondor Sum area and the northern zone in Manghete and Naomuhunni areas. They have been attributed to the subduction of Early Paleozoic oceanic crust. Blueschists from Ondor Sum and Naomuhunni are characterized by occurrence of sodic amphibole coexisting with epidote, albite, chlorite, calcic amphibole (in Ondor Sum) and muscovite (in Naomuhunni). Blueschists in Manghete contain porphyroblastic albite with inclusions of garnet and epidote in a matrix dominated by calcic–sodic amphibole, epidote, chlorite, albite and muscovite. Phase equilibria modeling for three blueschist samples using pseudosection suggest that the AlM2 contents in sodic amphibole can be used as a good barometer in the limited assemblage involving sodic amphibole+actinolite+epidote+chlorite+albite+quartz under pressures <4–6kbar, while this barometer is largely influenced by temperature and bulk Fe2O3 contents in the actinolite-absent assemblage sodic amphibole+epidote+chlorite+albite+quartz of higher pressure and the AlM2 contents are not pressure-controlled in the albite-absent assemblage sodic amphibole+epidote+chlorite+quartz under pressures>7–10 kbar. In the sodic amphibole-bearing assemblages, the NaM4 contents in sodic amphibole mainly decrease as temperature rises, being a potential thermometry. The calculated pseudosections constrain the P–T conditions of blueschists to be 3.2–4.2kbar/355–415°C in Ondor Sum, 8.2–9.0kbar/455°C–495°C in Manghete and 6.6–8.1kbar/420–470°C in Naomuhunni. These P–T estimates indicate a rather high geothermal gradient of 18–25°C/km for the blueschist metamorphism, being of intermediate P/T facies series. Available zircon U–Pb age data suggests that the protoliths of blueschists were formed later than Late Paleozoic–Early Mesozoic and metamorphosed soon afterwards. An alternative interpretation for the tectonic implication of blueschists in central Inner Mongolia is that they may be a new type attributed to closure of limited ocean basins and do not represent a tectonic regime occurred in conventional subduction setting.
Metamorphic P–T trajectories of high–P rocks can well constrain the exhumation mechanism of rocks and thermal structure in a subduction zone. The Yuli Belt in eastern Taiwan is regarded as an ...ophiolitic mélange related to the subduction of the South China Sea Plate beneath the Philippine Sea Plate, but the metamorphic evolution of the high–P rocks therein is still controversial. Two glaucophane schists from the Tamayen block in the Yuli Belt, are chosen for detailed studies of petrography, mineral composition and phase equilibria modelling, and addressing the metamorphic evolution. The glaucophane schists show coarse-grained amphibole porphyroblasts that distribute randomly in a matrix consisting of amphibole, epidote, garnet, phengite, chlorite, albite and quartz. Amphibole porphyroblasts are characterized by core–mantle–rim zoning from sodic-, calcic- to sodic-amphiboles. Three metamorphic stages are recognized, involving prograde to the peak, post-peak decompression and subsequent cooling. The prograde to the peak stage is constrained to occur in lawsonite- and omphacite-bearing assemblages with the peak conditions of 2.1–2.3 GPa/530–560 °C on the basis of the garnet zoning and the maximum Si content in phengite. The post-peak decompression was first dominated by dehydration reactions with the expense of lawsonite and omphacite and producing glaucophane, followed by decompression in fluid-absent fields to 0.6–0.9 GPa/500–550 °C with the growth of calcic amphibole. The subsequent cooling is inferred from the regrowth of glaucophane that rims amphibole porphyroblasts. The glaucophane schists share clockwise P–T trajectories with evident isothermal decompression, and the peak conditions correspond to a low geothermal gradient of ∼250 °C/GPa, representing the metamorphic evolution within a mature subduction zone. The high-P rocks in the Yuli Belt experienced two exhumation stages: firstly, the rocks were isothermally exhumed via a matured subduction channel from ∼70 km to ∼30 km depth and incorporated into the base of the accretional wedge during 12–9 Ma; and then, further exhumation occurred through thrusting and erosion in response to the arc-continent collision started from ∼6 Ma.
•Glaucophane schists (Taiwan Orogen) show peak P-T conditions of 2.1–2.3 GPa/530–560 °C.•They experienced a post-peak isothermal decompression to 0.6–0.9 kbar/500–550 °C.•They were firstly exhumed along subduction channel and then uplifted via thrusting.
ErbB2 overexpression identifies a subclass of breast cancer as ErbB2-positive that is frequently associated with poor prognosis. Current ErbB2-targeted therapies have profoundly improved patient ...outcomes, but mutations occurring in ErbB2 have been shown to confer drug resistance. Induction of ErbB2 degradation was proposed as an intriguing strategy to battle with ErbB2-positive breast cancer and reduced mutation-incurred drug resistance. Although multiple HSP90 inhibitors have been demonstrated to effectively trigger ErbB2 degradation, none succeeded in the clinical evaluations. To develop novel ErbB2-targeting strategies, we investigated the endocytic degradation and reversible ubiquitylation of ErbB2 in breast cancer. In this study, we reveal that HSP90 inhibition leads to efficient ubiquitylation and endocytic degradation of ErbB2 through the canonical endo-lysosomal route. USP2 associates with internalized ErbB2 and prevents its lysosomal sorting and degradation via exerting deubiquitylase activity. Accordingly, the USP2 inhibitor ML364 is capable of inducing ErbB2 ubiquitylation and accelerating its turnover. ML364 potentiates the pro-degradation effects of HSP90 inhibitors on ErbB2 and hence sensitizes ErbB2-positive breast cancer cells to HSP90 inhibition. The combination of USP2 and HSP90 inhibitors effectively restrains ErbB2-positive breast cancer xenograft growth in vivo. Based on these observations, we conclude that USP2 safeguards ErbB2 surface levels by antagonizing its ubiquitylation-mediated endocytic degradation, which can be exploited to design novel therapeutic strategies against ErbB2-driven malignancies as combinatorial treatment with HSP90 inhibitors.
Calcium silicate hydrate (C–S–H) gels, the main binding phase of cement paste, determine the mechanical properties of cementitious materials. In order to obtain the cohesive force in C–S–H gel, ...molecular dynamics was carried out to simulate the uniaxial tension test on C–S–H model along
x
,
y
and
z
direction. Due to the structure and dynamic differences of the layered structure, C–S–H model demonstrates heterogeneous mechanical behavior. The calcium silicate layer, constructed by Ca–O and Si–O ionic-covalent bonds, has stronger cohesive force than that of interlayer H-bond network. In addition, composition influence on mechanical performance has been investigated by variation of the Ca/Si ratio. High calcium content, de-polymerizing the silicate chain structure in C–S–H gel, weakens uniaxial tension strength and elastic modulus in three directions. More water molecules penetration into the defective silicate region further reduces the mechanical properties of C–S–H gel at high Ca/Si ratio. Composition analysis at nano-scale can provide molecular insights on the cementitious materials design with different Ca/Si ratios.
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